FTIR Spectrophotometry Research Articles

Copper Nanoparticle Catalysed Aerobic Oxidation of α-pinene

A green aerobic-oxidation of alpha-pinene using air and catalyzed by copper nanoparticle (CuNP) was studied. The study involved preparation and characterization of copper nanoparticle with three different calcination temperatures (300, 500 and 800°C). Nanoparticle characterization was conducted using FTIR spectrophotometry and SEM-EDX analysis. Evaluation of the catalytic activity was done using direct air-bubbled to the alpha-pinene with and without catalyst. It was found that oxidized alpha-pinene was formed as the major product.

The Effect of Parameter Combinations (Carbonization Temperature - Chemical Activator) on Degree of Graphitization, Aromaticity, and Fungsional Group of Rose Petal (Rosa sp) Based-Activated Carbon

Activated carbon is a porous material which is produced from the carbonization of organic compounds by involving the activation process. Activated carbon can be used as an absorbent of heavy metal cations, anions, and organic compounds. Quality of activated carbon is determined by the crystal structure, aromaticity, and its surface functional group. Activated carbon consists of amorphous and graphite structures. The graphite structure in activated carbon is important because it determines its thermal stability. Content of graphite structure in the activated carbon is stated as degree of graphitization (DOG). Aromaticity (fa) is related to amount of carbon atoms which form graphene layers in the activated carbon. The oxygenated functional groups of the activated carbon determines its hydrophilic / hydrophobic nature. Purpose of this research is to learn effect of carbonization temperature - chemical activator (ZnCl2) combination on degree of graphitization, aromaticity, and functional group on activated carbon. This research was conducted by using a pink rose flower precursor, at activator/precursor mass ratio of 0.1 at carbonization temperature of 400, 600 and 800°C for two hours under nitrogen gas stream. Characterization was carried out with FTIR spectrophotometry and X-ray diffraction. The DOG and aromaticity were calculated based on intensity of the difractograms. The characterization with FTIR spectra related to –OH and aromatics C=C bond vibrations. The highest DOG was obtained by the activated carbon resulted at 400°C, i.e. 92.31%. However, no significant different of the aromaticity, about 0.42 to 0.50.

A Spectral, Optical, Microscopic Study, Synthesis and Characterization of PVC Films Containing Schiff Base Complexes

In this work, synthesis of conducting polymeric films namely, PVC thin films was carried out containing Schiff base (L) with Cu2+, Cr3+, Ni2+, Co2+, in addition to inspecting the possibilities of measuring energy gap values of PVC-L-M with variety metal ions. These new polymeric films (PVC-L-M) were characterized by FTIR spectrophotometry, energy gap and surface morphology. The optical data recorded that the band gap values are influenced by the type of metals. All modified films have a red shift in optical properties in the ultraviolet region. The PVC-L-Co(II) was the lowest value of the optical band gap, 3.1 eV.

A Spectral, Optical, Microscopic Study, Synthesis and Characterization of PVC Films Containing Schiff Base Complexes

In this work, synthesis of conducting polymeric films namely, PVC thin films was carried out containing Schiff base (L) with Cu2+, Cr3+, Ni2+, Co2+, in addition to inspecting the possibilities of measuring energy gap values of PVC-L-M with variety metal ions. These new polymeric films (PVC-L-M) were characterized by FTIR spectrophotometry, energy gap and surface morphology. The optical data recorded that the band gap values are influenced by the type of metals. All modified films have a red shift in optical properties in the ultraviolet region. The PVC-L-Co(II) was the lowest value of the optical band gap, 3.1 eV.

IDENTIFIKASI SENYAWA KIMIA FENOLIK DALAM EKSTRAK ETIL ASETAT KULIT BUAH JENGKOL

Jengkol (Archidendron pauciflorum (Benth.) I.C Nielsen) is a plant that is already familiar in Indonesia and is widely used as a processed food that is quite popular. One of the underutilized parts of the jengkol plant is the skin. Jengkol fruit peel contains alkaloid compounds, flavonoids, tannins, glycosides, sapoinin and steroids or triterpenoids. The purpose of this study was to determine the content of chemical compounds in ethyl acetate extract of jengkol fruit peel, and to test antioxidant activity by DPPH free radical reduction method.The results of isolation, purification in ethyl acetate extract of jengkol fruit skin does not provide activity as an antioxidant. The results of the analysis using FTIR spectrophotometry, Gas chromatography-Mass Spectrometry (GC-MS) and Nuclear Magnetic Resonance Spectroscopy (1HNMR). Keywords: Antioksidan ,archidendron pauiflorum (Benth) I.C Nielsen, jengkol, (1- (2,6-dihydroxy, 4methoxy phenyl) decane-1-one).

Synthesis of Nanosilica from Padas Stone to Reduce The Total Organic Carbon of Palm Oil Waste

Padas stone is one of the natural mineral containing 67.5% of SiO2 compounds. In this research, synthesis of nanosilica was carried out by sol-gel method asistanced by 2.45 GHz microwave radiations with low (10%), medium (50%) and high (100%) power at 30 and 60 minutes of contact times. It was analyzed by XRD, BET, FTIR spectrophotometry and SEM. The synthesized silica was then used as absorbent for total organic carbon (TOC) of palm oil waste. The results show that the synthesized silica was a mixture of cristobalite and quartz type minerals according to ICDD No. 00-003-0271 and 01-083-287. The surface area and silicon dioxide contains are 12.174 m2/g and 76.325% for silica without microwave assistance (SiO2-TPMW); 12.796 m2/gand 86.385% for silica with 30 minutes on 10% microwave assistance(SiO2 -MW 10A); 12.735 m2/gand 86.254% for silica with 60 minutes on 10% microwave assistance (MW 10B); 13,659 m2/gand 87.211% for MW 50A; 13,583 m2/g and 86.684% for MW 50B;7.883 m2/gand 57.527% for MW 100A; also 8.752 m2/g and 37.725% for MW 100B, respectively. The use of silica as an absorbent of TOC shows the effectiveness of 62.89% (TPMW); 63.68% (MW 10A); 62.96% (MW 10B); 65.25% (MW 50A); 64.61% (MW 50B); 62.37% (MW 100A) and 61.18% (MW 100B) from the initial TOC of 1520 mg/L. Keywords: synthesis, nanosilica, padas stone, total organic carbon, oil waste.

Sintesis Senyawa Turunan Amoksilin Dan Uji Aktivitas Antibakterinya Terhadap Bakteri Salmonella typhi

The synthesis of amoxicillin derivate has been done by reacting amoxicillin with 4-t-butylbenzoil chloride. The product was characterized by organoleptic test, melting point determination, TLC, UV/Vis Spectrophotometry, and FTIR Spectrophotometry. Antibacterial activity of amoxicillin derivative against Salmonella typhi were tested using dilution method. Result showed that the product has characteristic as follow: light yellow powder, bitter bite, melting point of 132 °C, Rf value of 0.86, pH value of 7.7, maximum wavelength (uv) of 286 nm. Moreover, FTIR spectra of amoxicillin derivate exhibited peaks at 3271 cm-1 (-NH amine), 2962 cm-1 (-CH aromatic), 1633 cm-1 (-C=O ketone), and other. Antibacterial test showed that amoxicillin derivate was unable to form a clear zone around the disc paper. Amoxicillin derivate cannot be used for the treatment of Salmonella typhi.

Synthesis and characterization of Ni(II) complex functionalized silica-based magnetic nanocatalyst and its application in C-N and C-C cross-coupling reactions.

A new magnetically recoverable silica-based nickel(II) nanocatalyst was synthesized by a simple cost-effective procedure, which was characterized by TEM, SEM, XRD, VSM analysis, and FT-IR spectrophotometry. The catalytic activity of the prepared Ni(II) nanocatalyst was tested in two complementary reactions: C-N Chan-Lam cross-coupling of phenylboronic acid with aryl amines and C-C Suzuki-Miyaura cross-coupling reaction of phenylboronic acid with aryl halides. The catalyst was easily recovered by magnetic separation and reused for five times. It demonstrated better catalytic activity in the C-N Chan-Lam reaction compared to C-C Suzuki-Miyaura reaction. Ease of recovery and reusability up to five cycles without noticeable loss of performance in the C-N cross-coupling reaction make the present protocol beneficial both industrially and environmentally. In this paper, a new magnetically recoverable silica-based nickel(II) nanocatalyst was synthesized and applied in two complementary reactions: C-C Suzuki-Miyaura reaction and C-N Chan-Lam reaction. The difference in catalytic activity makes it possible to use this catalyst for cases that are prone to both reactions and selectively create the desired product.

FTIR DERIVATIVE SPECTRA ANALYSIS OF BEEF AND PORK PROTEIN

According to recent investigations on beef adulteration, there are many cases found that beef mixed with pork . PCR (Polymerase Chain Reaction) as the method of choice for such analysis are considered to be relatively expensive and less practical. It would be necessary to develop a simple alternative methode which could differentiate beef and pork. The purpose of this research was to analyze beef and pork using FTIR spectrophotometry. Main FTIR spectrum and first derivative spectrum were used for analysing beef and pork of fresh samples (unprepared), crushed sample and denaturated by heating. The result indicate that FTIR spectrum was relatively repeatable for all prepared samples. Infrared absorption bands of beef is more complex than pork which almost all of the infrared absorption bands found in the spectrum of beef, except for the presence of absorption at wave numbers 1068-1017 cm-1 and clarified on first derivative spectrum. This unique peak considered could be used as reference peak for analysing pork protein or adulteration of beef with pork. Keywords : beef, pork, FTIR spectrophotometry, first derivative spectra

FTIR Spectrophotometry as a Green Tool for Quantitative Analysis of Drugs: Practical Application to Amoxicillin

Amoxicillin is an antimicrobial agent that belongs to the penicillin compounds. Its bactericidal action causes a destruction of the cell wall of bacteria. It is widely used in clinical practice, and it belongs to the Brazilian National List of Essential Drugs (RENAME). In literature, there are some green analytical methods for the amoxicillin analysis; however, none of them is focused on its quantification in capsules. Therefore, the aim of this study was to validate an environmentally friendly analytical method for the analysis of this antimicrobial action in capsules, using spectrophotometry in the mid-infrared region. The analyses were performed in the spectral range of 1815–1736 cm−1, and the samples were analyzed as potassium bromide pellets. The method was validated according to the ICH guidelines and Brazilian legislation. Linearity, selectivity, precision, accuracy, and robustness were evaluated and showed adequate results for method validation, in a concentration range of 0.5–1.5 mg/pellet. Thus, it is concluded that the validated spectrophotometric method is able to quantify amoxicillin in capsules. In addition, it is a fast, economical, and environmentally friendly method, since it does not use organic solvents, and it can be used for quality control of routine analysis of this drug.

Standardization of Dyeing Process Variables for Dyeing of Cotton Khadi Fabric with Aqueous Extract of Babul Bark (Acacia Nilotica L.)

Study of dyeing process variables and its standardization is essential for establishing scientifically reproducible standard method of dyeing cotton fabric with specific natural dye like babul bark containing vegetable gallic/tannic acid residue besides natural color component. Effects of different single and combined double mordanting and dyeing process variables on surface color strength and color fastness properties after dyeing cotton khadi fabric with aqueous extract of Babul Bark (Acacia Nilotia L.) as natural dye were studied in the present work. Potash alum, aluminium sulphate and stannous chloride were used as metallic salt mordant and Harda (Myrobolan) was used as natural mordant assisting agent. Relevant results indicate that application of overall 15% dosages of Harda and aluminium sulphate in 75:25 ratio offers maximum K/S value (5.44) and overall good color fastness (3–4 or higher) than other combination studied. After finalizing the mordants, dyeing process variables were studied for standardization of the dyeing process using babul bark extract. Relevant results indicate that this particular natural dye (babul bark) renders better color strength for optimized conditions of dyeing with dyeing time: 60 min, dyeing temperature: 65 °C, at MLR: 1:30, dye bath pH: 5.0, optimum dye conc.: 30% (based on dry weight of source materials) and common salt—5%. Study of FTIR and Atomic absorption spectrophotometry (AAS) for the said natural dyed cotton khadi fabric with babul bark indicate presence of metallic mordant and tannin content for explaining the observed results showing dye-fibre-mordant complex formation besides hydrogen bonding as well.

Isolasi Kitosan Dari Tudung Jamur Merang (Vollvariella Volvaceae) Dan Aplikasinya Sebagai Absorben Logam Timbal (Pb)

Chitosan isolated from mushroom (Vollariella volvaceae) as adsorbent of lead (Pb) metal has been done. The isolation of chitosan was obtained 2.94% from total weight of mushroom. Fungtional groups of chitin and chitosan were indentified by using FTIR spectrophotometry. The chitosan had 74.66% degree of deacetylation and 2.09 x 104 g/mol viscosity molecular weight. The experimental data of the chitosan as adsorbent for Pb metal were correlated with the Langmuir and Freundlich isotherm model. The maximum adsorption capacity of Pb based on the Langmuir isotherm model was 2.66 mg/g.

Study of Organic Substance (Myrmecodia pendans) Extraction Using Soxhletation Method as an Organic Inhibitor

Extract of natural substance is currently being developed as an organic inhibitor. Organic inhibitor can be used to inhibit corrosion rate of metallic material especially steel. The purpose of this study is to analyze the effectiveness of soxhletation extraction methods and the quality of inhibitor of Sarang Semut (Myrmecodia pendans) extract. The variations implemented in this research were the composition of the solvent-material and the content comparison of flavonoid compounds. The results of Sarang Semut (Myrmecodia pendans) extract inhibitor using soxhletation extraction method was observed qualitatively and quantitatively This research used soxhletation extraction method, simplicia Sarang Semut (Myrmecodia pendans) powder as the organic substance, and a mixture of acetone and distilled water as the solvent. Ratio variation of the solvent-substance composition used are 1:10, 1:15, and 1:20. Tests used in this study were Extract Parameters, FTIR, TLC and UV-Vis Spectrophotometry and weight loss. The highest yield was shown when using 1:10 ratio which was 13.943%, the total ash content and the lowest extracted water content shown at a ratio of 1:10 with amount of 4.26% and 4.2483%. FTIR test results indicated functional groups of flavonoids compounds and TLC test showed positive results of Flavonoid compounds which were characterized by blackish discoloration. The highest percentage of flavonoid compounds of 0.22025% found at the 1:10 ratio. The highest efficiency inhibition happened when weight loss testing showed 500ppm with the result of 84.3%.

1-(4-Hexylbenzoyl)-3-methylthiourea

The 1-(4-hexylbenzoyl)-3-methylthiourea compound has been successfully synthesized by reacting 4-hexylbenzoyl chloride and 1-methylthiourea via the reflux method using a triethylamine catalyst. The 1-(4-hexylbenzoyl)-3-methylthiourea compound was identified by UV-visible, FT-IR, 13C/1H-NMR and Mass spectrophotometry. From the activity test on four cancer cell lines (HeLa, T47D, WiDr and MCF7 cell), it could be seen that it had better activity on four cancer cells than the control, hydroxyurea.

The performance of derivate FTIR spectrophotometry method compared to colorimetry for tranexamic acid tablet content determination

Recently, FTIR reported has been established as a direct content determination for some tablet dosage forms. In the method, infrared transmittance spectra was converted into the derivated absorbance form. In this present research, the method’s performance was investigated to quantified tranexamic acid in its tablet dosage form directly. The result then was compared to the colorimetry, which has been developed by another researcher. Correlations between the two methods were analyzed using t-test. The good linearity was shown at concentration range of 0.5 - 1.75% w/w at the wave number of NH group. Furthermore, the recovery, intra- and inter-day precision also fulfilled the validation requirement. Meanwhile, LOD and LOQ of the method were 0.0531%w/w and 0.1770%w/w. These methods were compared with colorimetry has been established before. Afterwards, the t-test proved no significant difference of content determination yielded, between these two methods. In conclusion, FTIR can be used for quantify the content of tranexamic tablet, more accurately than colorimetry, which has been developed before. Moreover, FTIR method also has advantages such as easier, simpler, faster and cheaper than the colorimetry method. Â

Antimicrobial cholic acid derivatives from the Pitch Lake bacterium Bacillus amyloliquefaciens UWI-W23

Six cholic acid derivatives (1–6) were isolated from broth cultures of Bacillus amyloliquefaciens UWI-W23, an isolate from the Trinidad Pitch Lake. The compounds were extracted via solvent extraction and/or XAD resin adsorption and purified using silica gel column chromatography. Their structures were elucidated using 1D, 2D NMR and ESI-MS spectrometry and FT-IR spectrophotometry. One of the compounds, taurodeoxycholate (2) is for the first time being reported from a bacterial source while deoxycholate (4) is for the first time being reported from a Gram-positive bacterium. The other compounds have not been previously isolated from Bacillus spp. viz. cholate (1), taurocholic acid (3); glycodeoxycholic acid (5) and glycocholic acid (6). All six compounds exhibited antimicrobial activity against P. aeruginosa and B. cereus with MICs ranging from 7 to 250 µg/mL. Cholate (1) also showed activity against MRSA (MICs = 125 µg/mL) and glycocholic acid (6) against S. cerevisiae (MICs = 15.6 µg/mL).

A sensitive and selective probe for visual detection of Cu2+ based on 1, 8-naphthalimidederivative

A novel 1, 8-naphthalimide-based derivative, named as (E)-6-(2-((1H-pyrrol-2-yl)methylene)hydrazinyl)-2-(2-hydroxyethyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (HHBD), was synthesized via facile condensation and substitution reactions. It showed high sensitivity and selectivity to Cu2+ in CH3CNH2O (v/v = 3:7, pH = 7.0) solution, and the hypsochromic shift of the absorption band & the enhancement of the fluorescence emission intensity were distinct for the detection of Cu2+ even in the presence of other competitive metal ions, such as Ag+, Al3+, Ca2+, Co2+, Cr3+, Fe2+, Fe3+, K+, Li+, Mg2+, Na+, Ni3+, Zn2+. The binding stoichiometry between HHBD and Cu2+ was calculated from Job’s plot and the complexation mechanism was explored by 1H NMR and FTIR spectrophotometry. Furthermore, HHBD binding capability with Cu2+ was further demonstrated using DFT calculations. The probe was applied successfully in real water samples assay. Strip papers were also designed and used to detect various concentrations of Cu2+ aqueous solution, whose color change showed their potential application for on-site detection of Cu2+ in pollution water.

Multi-scale and multi-technique analysis of the thermal degradation of poly(ether ether ketone)

The thermal degradation of PEEK has been studied in rubbery state in wide ranges of temperature (between 180 and 320 °C) and oxygen partial pressure (between 0.21 and 50 bars). On one hand, the thermal ageing mechanisms have been analysed and elucidated by FTIR spectrophotometry and by differential scanning calorimetry (DSC) on sufficiently thin PEEK films (between 10 and 60 μm thickness) to be totally free of the effects of oxygen diffusion. Oxidation occurs on aromatic rings causing the growth of five new IR absorption bands centered at 3650, 3525, 1780, 1740 et 1718 cm−1 and attributed to the stretching vibrations of the O-H bonds of phenol and benzoïc acid, and the C-O bonds of benzoïc anhydride, phenyl benzoate and fluorenone respectively. In addition, oxidation leads to a large predominance of crosslinking over chain scissions resulting in a sharp increase of Tg. This reduction in molecular mobility prevents the annealing of PEEK, in particular when the temperature of exposure is higher than the onset of the melting endotherm. On the other hand, the consequences of oxidation on the elastic properties have been analysed and elucidated by micro-indentation on polished cross-sections of PEEK plates of 3 mm thickness. The diffusion control of oxidation leads to the development of profiles of Young's modulus within the sample thickness, which correlate perfectly with the changes in crystallinity and macromolecular architecture determined at lower scales. The validity of the Tobolsky's relationship is demonstrated.

Laser versus scalpel cleaning of crustose lichens on granite

This paper addresses the evaluation of the cleaning of crustose lichens developing on granite. The evaluation was performed considering the effectiveness of the cleanings and harmfulness exerted on the granite. The laser cleaning of lichen was compared with the most conventional procedure, scalpel. The combination of both procedures was also tested. The study, which was carried out with two different species of crustose lichen, was also focused on the influence of the intrinsic characteristics of the lichen on the effectiveness.The cleanings were evaluated by optic and electronic microscopies, FTIR and colour spectrophotometry. A previous characterization of the lichen and its interaction with the granite using those analytical techniques were also performed. The laser cleaning effectiveness depends on the coverage and the colour of the lichen; also, the prior mechanical weakening of the lichen by scalpel seemed to improve the laser cleaning. The darkest lichen was satisfactorily removed by laser and with the combined cleaning. Conversely, the lightest lichen was more difficult to extract with laser than the darkest lichen, being necessary to apply both methods sequentially. Despite laser and the combination of methods cleaned satisfactorily the surface, they were unable to eliminate the thalli into fissures.

THE USE OF CITRIC ACID MODIFIED BACTERIAL CELULLOSE AS AN ENVIROMENTALLY FRIENDLY ADSORBENT

<p><strong>Abstract</strong></p><p>The use of nata de coco as an ester cellulose raw material through esterification using various of carboxylic acids has been widely conducted. In this study, it was used citric acid with three carboxyl groups. This aim research were to determine the optimum reactant composition and to compare the cellulose citrate properties toward bacterial cellulose and commercial ester cellulose. Esterification at mass ratio of nata : citric acid were 1 : 1 up to 1 : 9 were conducting at temperature of 150<sup>o</sup>C. The optimum ester cellulose produced, were then characterized based on the FTIR spectrophotometry, hydrophobicity and degree of crystallinity. Furthermore, the surface area has been determined in order to find out its potency as an adsorbent .The result revealed that reaction using citric acid has affect on chemical structure and hydrophobicity. The increase of hydrophobicity and degree of crystallinity was influenced by citric acid added. On the other hand, it was obtained that cellulose citrate could be develop as an adsorbent.</p><p><span style="text-decoration: underline;">Keyword</span>: <em>cellulose, esterification, citric acid, adsorbent </em></p>